William a



(No Nlodel.)

W. A. KNOWLES.

I DENTAL ENGINE. A No. 372,317. Patented Nov. 1. 1887.

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wiLLIAMA. KNowLEs, or ALAMEDA, CALIFORNIA.

DENTAL ENGlNE.

` SPECIFICATION forming part of Letters Patent No. 372,317, datedNovember 1, 1887.

l Application tiled May 14, 1887. Serial No. 238,166. (No model.)

T0 all whom, it may concern.-

Be it known that I, WILLIAM A. KNowLEs, a. citizen of the United States,residing in the city and countyof Alameda and State of California, haveinvented a new and useful Dental Engine,'of which the following is aspecifica:

tion.

My invention relalesto improvements in dental engines, which will beunderstood by reference to the accompanying drawings and the lettersreferring thereto.

Figure 1 is a side elevation showing the crane-arm in section and brokenofi' and a broken part of the cable-sleeve; Fig. 2, a side elevationshowing the cable-sleeve and cablerod broken off; Fig. 3, alongitudinalsectional elevation of the same, as shown in Fig. l; andFig. 4` is a side elevation of a machine constructed in the simplestform, without any means of tipping the cable down when not in use. Fig.5 is an enlarged broken view of the tip-down bracket M, designed to showthe stopspring S more clearly than it is shown in Figs. 1 and 2.

A represents the end of any crane lever or arm to which my'improvementis attached;B, the top frame for the reversing-gear and driving-pulley;C, the set-screw for the top of the driving-spindle; D,' the lock-leverfor the setscrew O, to preventthe same from loosening; E, thelock-spring, which operates the locklever D to hold it in place; F, thespindle for the driving-pulley and reversinggear; G, the upper, and H'the lower, bevel-wheel of the reversing-gear; I, the driving-pulley; J,the driving-cord; K, thebevel-pinion which drives the cable; L, thesupporting-bracket sleeve shown in Fig. 4, and M the pivoted bracketshown in Figs. l, 2,. and 3; N, the pivot, by means of which the bracketM is hinged; O, the lock-lever for holding the bracket M in gear; P, thethumb-piece for operating the 1edriving pinion; V, the head-block forthe cable-sleeve; W, the eablesleeve.

X represents the adjusting-collar; Y, the set-screw for setting the adjlisting-collar fast.

Z represents the stop-rest by which the machine is held in gear.

A represents the vertical guide-slot in the 4bracket M, to allow thepost U to be raisedY and lowered and the gear to be reversed.

B represents the adjusting-pin which is attached to the post U, andoperates through the vertical guideslot Aand the cam guideslot R.

C represents the'cable-rod.

D represents the spring which returns the lock-lever O.

E represents the hanging pivotpost, which forms the bearing for thesupporting-bracket sleeve L and the step or bearing for the spindle F torevolve in.

G represents a stop.

The following is the operation of my im! proved engine: In Fig.- l thepinion K is shown in gear with the bevel-wheel H, and the driving-cord Jrevolves the pulley l continuously in the same direction. Thethumb-piece T is now thrown out to the left and held in that positionbythe cam or inclined spring-cam S, while the pin B', being held at oneposition laterally, is forced down by means of the angular slot R, thuskeeping the pinion K in gear with the bevel-wheel H and revolving thesame in a corresponding direction. To reverse the action of the pinionK, the thumb-piece T is operated, turning the cam-sleeveQand moving theslot R over the pin B', thereby raising the pinion K up against thewheel G and caus- .ing it to revolve in the opposite direction.

As the thumb-piece T is passed over the spring cam-stop S, the stop Srises up behind the same, thus holding it in place and the pinion K ingear, as has been shown. It will be seen that as the supporting-sleeve Lhas its bearing upon the hanging-post E and revolves concentricallywiththe spindle F, it may be revolved about four-fifths of a revolution,thereby allowing the drill-cable to be used in any rel quired directionhorizontally.

The object of employing the collar X is to .any unnecessary verticalmovement in the f1t- ICO -the pivot N.

ting upon the hangingpost E. Vhen it is required to tip the cable down,(as is euston1- ary for preserving the ilexible eable,) the looklever Ois tipped down by pressing the thumbpiece I), and the stop-rest Z isreleased and the cable is turned down, the bracket turning upon Vhenraised again, it is only necessary to raise the cable-sleeve XV to ahorizontal position,when the stop rest Z passes to the end ofthelock-lever O, and the spring D throws the lock -lever O in behind thesame, thereby locking the pinion K in gear with either the bevel-wheel Gor H, as it may be set.

The set-screw Gis furnished with a concave bearing for the top of thespindle F,and when turned tothe right point for the required bearing thecatch-lever D is dropped between the eogs, and holds the saine fromturning back. The lever D is held in Contact by the spring E, as shownin Figs. 1 and 3.

Having thus described niy invention, what I claim, and desire to secureby Letters Patent, is, in dental engines- 1. The combination, with acrane or supporting-arm A, of the top franie, B, the conebearing C, thelock-lever D, the spring E, and the hanging pivotpost E', for thepurpose of supporting and adjusting the spindle F, and gear G, H, andconstructed and 0pcrated substantially as and l'or the purposes setforth.

2. The Combination, with a crane or supporting-arm, A, ofthe top frame,B, the conebearing C, the loeklever D, the spring E, the

hanging pivot-post E', and the adjusting-e01- lar X and set-screw Y, forthe purpose of supporting and adjusting the spindle F, the gear G, H,and I, and furnishing a bearing and adjustment for the supportingsleevebracket L, constructed and operated substantially as and for thepurposes set forth.

3. The combination, with a crane or supporting-arm A, having a topframe, B, of a eene-bearing C, the lock-lever D, spring E, the hangingpivot-post E', the adjusting eollar X, the supporting-bracket sleeve L,with lever O and P, and spring D', for the purpose of adjusting andoperating the tip down bracket M, constructed and operated substantiallyas and for the purposes set forth.

4. The bracket M, hinged at N, having the spring eain or stop S, thevertical slot A,and the lock-notch Z and stop G', in Combination withthe earn-sleeve Q, having the angular slot R, and thumb piece T, andwith the attaching pivot-post U, having the adjusting-pin B',and withthe supporting-brachet sleeve L, having the lock-lever O, withthumb-piece l), and spring D, for the purpose of releasing the tip-downbracket M, allowing the eablesleeve V to swing horizontally, and forreversing the movement of the drill-cable, constructed and operatedsubstantially as and for the puposes set forth.

YVILLTAM A. KNO\VLES.

Witnesses:

JOHN H. RnDs'roNn, J. H. BLOOD.

